Bridge deck design - help needed 1

[5laura5]

I have been tasked with designing a 12m span single carriageway highway bridge deck. The deck construction details have been left entirely down to me and being more form an environmental background i am very uncertain as where to look or how to go about the design, other than knowing it must be designed to British Standards.

Any tips, pointers or guidance on this matter would be greatly appreciated.

 

[rowingengineer]

5laura5,
You will need to grab the senior engineer in your office and have a discussion with him, we help a little and give a starting point, but you really need to understand the local conditions, these have big impacts on design. These are such things as, are you replacing an existing, thus time down is of major importance (hence precast would be a good idea), What is the road structure up to the big like, can it handle construction loads (assume in your case yes , but on larger bridges no), what is the design life of the structure? What is the skew? Is it curved? These affect the performance of the bridge in bending. What are you local contactors good at, ie what is the most common bridge around, this will help you ensure you design knowing it can be built, in my area (Australia), it is box construction. I could go on all day bt below are some starting thoughts that you will need to discuss with your senior engineer
As a starting point, attacking a bridge structure you will need to think of the following and more.
1. Deck? Generally you will have a concrete deck with a wearing surface on top. This doesn’t have to be the case but I like it.
2. Structure? What is your main structure; you can have box concrete, composite steel, Timber, monolithic to name a few.
3. Durability aspects will come into you above decisions, ie freeze thaw, distance to the coast.
4. Foundation requirements can have an impact is the soil is soft, and you have to pile.
These points will at least give you the starting area’s to talk to your senior engineer. Good luck, let us know how you go.


When in doubt, just take the next small step.

 

[graybeach]

5laura5,

Can you get hold of any standard details from the governing agency? Here in New York State, the DOT has lots of guidance and standard details about deck design on their website. You can check out that info as a starting point. Search for NYSDOT Bridge Manual, and also check out the BD sheets.

 

[Qshake]

My experience in the UK is that most times a single span bridge will have an adjacent deck beam superstructure and not a typical US slab on girder type of construction.

In general, you need to get a set of example plans from your senior engineer and see what applies to your situation and discuss the load path and code requirements for design.

Good Luck.

Regards,
Qshake

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